1. Field of the Invention
The present invention relates to an apparatus and method for manufacturing tempered glass, and more particularly, to an apparatus and method for manufacturing tempered glass, in which the difference in temperature between the inside and outside of a glass substrate is maximized, so that tempering is more completely realized through quenching.
2. Description of Related Art
In general, tempered glass has resistance to pressure and changes in temperature superior to those of normal glass substrates, and, when broken, shatters into small fragments having the form of particles, thereby making it less likely to create a hazard due to shards. Therefore, tempered glass is widely used for solar cells, display devices, automobiles, buildings and the like.
A glass substrate is heated up to a temperature ranging from about 600° C. to about 900° C. in a heating chamber, and is then carried on a carriage into a cooling chamber, where air is ejected through air nozzles of an air cooling apparatus from above and below the heated glass substrate, so that the surface temperature of the heated glass rapidly drops to a temperature ranging from 200° C. to 400° C. Consequently, compressive strain is caused to remain in the surface layer of the heated glass, thereby manufacturing the tempered glass, the strength of which is increased so as to be superior to those of normal glass substrates.
However, the apparatus for manufacturing tempered glass of the related art is limited in its ability to increase the strength of the tempered glass, since it performs cooling using the air cooling apparatus, which takes in ambient air and then directly ejects it onto the glass. The strength of the tempered glass becomes higher when the glass is cooled more rapidly. In the related art, however, the heated glass is slowly cooled, since it is cooled using air that is at room temperature. Consequently, the tempering is incompletely carried out, thereby increasing the defective fraction of products. Moreover, this phenomenon becomes more serious in the summer when the temperature of the ambient air is higher.
The information disclosed in this Background of the Invention section is only for the enhancement of understanding of the background of the invention, and should not be taken as an acknowledgment or any form of suggestion that this information forms a prior art that would already be known to a person skilled in the art.